Re: Mandy Jane's Corner

I don't remember whether that one has anything to do with maths. I think you should leave maths to this site.That one seemed to me to be about dyslexia with a whole load of sub forums for dyslexic management issues.For now I think you ought to bring up anything about maths that you want me to discuss.

I have just looked again at the website I suggested and I can't see any sub forum in there to do with maths.

Re: Mandy Jane's Corner

A cubic metre is defined as being the volume of 100cm x 100cm x 100cm.

A litre can be regarded as the volume of a 10cm x 10cm x 10cm cube of something.

A decilitre is one tenth of a litre that is to say 10 times smaller than a litre and is 100 millilitres.

A centilitre is one hundredth of a litre that is to say 100 times smaller than a litre and is 10 millilitres.

A millilitre is one thousanth of a litre that is to say 1000 times smaller than a litre. One cubic centimetre = one millilitre

Although the millilitre is the same as a 1cm x 1cm x 1cm cube in volume notice that you cannot do thiswith a centilitre or a decilitre without an irrational decimal to make the unit length of such a cube despite this the total volume is a nice round number relative to the others.

Here is a summary of the terms on the left, then how many litres that is, then the perfect cube form of it witha side length from the cube root of the number of cubic centimetres, and in square brakets the method for gettingthe side length in cm of the perfect cube:

(One million millilitres make up a cubic metre notice you have to do 100 x 100 x 100 to get a million or 1000 x 1000)(one cubic metre = 100cm x 100cm x 100cm = 1,000,000 cubic centimetres or one million cubic centimetres or one million millilitres)

Mandy: It wouldn't hurt for you to read that bit above, but the maths of volume ratios in 3 dimensions goes rather beyond the scope of the level you are studying, but if it helps you learn it then by all means learn it in the above style and perhaps repeat the cube root calculations using a scientific or graphics calculator.

(Needless to say in practice even an engineer does not usually need to calculate something like that to 11 d.p.if you can only measure to 3 signifcant figures then the answer is going to have about the same accuracy)

Re: Mandy Jane's Corner

With temperature we can do Fahrenheit and Celcius (or Centigrade - which does your course use out of interest?).

To convert into Centigrade from Fahrenheit you do the following:

start with degrees F subtract 32 then divide by 9 and multiply by 5

To convert the other way it is:

start with centigrade divide by 5 multiply by 9 then add 32.

So for example: 32F is the temperature at which water freezes. Subtract 32 then divide by 9 and multiply by 5.Since we get zero the division and multiplication has no effect. We get 0C, or just zero Celcius/Centigrade.

Another example: 50F subtract 32 and we get 18. Then divide by 9. We get 2. Then mutiply by 5. We get 10.Answer: 10C or 10 Celcius or 10 centigrade.

What is 68 Fahrenheit in Celcius ? (From now on I will call it Celcius to save me time typing both versions.)

Notice that when converting Celcius into Fahrenheit we can do: 1.8 C + 32 = FWhen converting Fahrenheit into Celcius we can do: (F - 32) / 1.8 = CWhere C is the temperature in Celcius and F is the temperature in Fahrenheit. In other words using algebra for this conversion.Notice also that (9/5) = 1.8

(4) What is one pint converted into litres? (Hint: there are 1.7598 pints in one litre. This is using UK conventions not US conventions.)

1 / 1.7598 = 0.5682.... litresSo there are 0.568 litres in a pint to 3 d.p. using the UK imperial pint definition.

(Apparently the US convention is that there are 473 millilitres in a US liquid pint. In UK there are more millilitres than thatin a UK imperial pint. It is the UK version that I was referring to in question 4)

Notice that for instance with question (4): no of litres x 1.7598 = no of pintsno of pints / 1.7598 = no of litresI was taught to imagine 'dividing both sides of the equation by 1.7598' to get the second. More on that when you do algebra.(I have improved #1236 a bit let me know if you don't agree with any of it. However I believe it is all correct)

Re: Mandy Jane's Corner

Hi bob bundy mandy here i am finding the maths course hard to do? What do you think I should do? Do you think a college course would be good or not? Send me a message back on here or email me back please?